All 2st PWK Needle Comparison

NOTE: Some of my initial calculated values for the Keihin needles were off. They have been corrected, but some of the comments may refer to the earlier (incorrect) values.

I am trying to get my carb dialed in the last little bit on my WR, and I thought it might be a needle issue, so I took some measurements:

JD Blue, measured from the top clip:

Location (mm)Diameter (mm)
6.35 2.870
12.7 2.870
19.05 2.680
25.4 2.667
31.75 2.667
38.1 2.464
44.45 2.261
50.8 2.083
57.15 1.981
This works out to a base diameter of ~2.67-2.68, and an initial taper angle of about 1.7 degrees.

Then I looked up the specs for a CEL needle (I do not have one to measure, yet):

Location (mm)Diameter (mm)
0 2.705
6.35 2.705
12.7 2.705
19.05 2.705
25.4 2.705
30.8 2.705
38.1 2.516
44.45 2.350
50.8 2.184
57.15 2.018
63.5 1.851
The base diameter for a CEL is 2.705mm, and the taper angle is 1.5 degrees.

It looks like the CEL should also be leaner at idle and light throttle, due to the larger base diameter. Once you get onto the taper the needles are similar, although the JD is going to get richer a bit faster because the angle is a little bit steeper.

Can someone with a CEL measure it for me (or I guess I can just buy one, I'd like to try it anyway)? I will pull my JD red tonight and measure it to add to this info...

Ok, here's the measurements for the JD Red:

Location (mm)Diameter (mm)
6.35 2.870
12.7 2.870
19.05 2.680
25.4 2.667
31.75 2.667
38.1 2.464
44.45 2.261
50.8 2.083
57.15 1.981

It's pretty darn close to the JD Blue, the major difference that I see is the base diameter of 2.69 (vs. 2.67). So it'll be leaner around/off idle. The red looks a hair richer up top but it could be measurement error.

Here is some info about what is available and what the letter code(s) mean: http://www.jetsrus.com/a_jets_by_carburetor_type/needle_keihin_N427-48.html

For right now, I am going to try my JD red needle in the 1st clip position! If guys can run the CEL without blowing stuff up, that ought to be just fine.

Get the CEL and forget the red

I am going to order a CCL (same as CEL but 2 clips richer for more range). I am also going to order a DCL, which should be about halfway between the JD red and the CEL. It has the larger base of the CEL to lean out the low throttle a bit, but it also has a steeper taper to keep it rich up top like the JD, and it isn't as many clips off as the CEL.

Thanks guys! I will report back.

I still get a little rich with the cel in middle clip in the mid when temps are above 75. I probly should lower it a clip

I have tried a lot of different needles on my 300. In the woods i run the red JD needle now in 1st clip at sealevel and around 20 C. This needle is a bit smoother off throttle than the CEL. For maximum power the EEL was best, also shown on the dyno. This was used in ther winter for iceracing. i Think a CEM would be good as i feel that the red JD is a bit too rich on the base diameter. CEL in second clip is also very good for my riding. I Think many guys are just looking at the clip positions, but it would be better to laborate with different base diameters to get rid of the low speed bludder for example. No airscrew in the world is compensating for a too thin needle. I also use a G2 throttle grip. Very good for smoother engine response in tight woods! Another thing to do think about is that if you are using a more tapered needle you also have to use a smaller mainjet. From C-taper to D-taper is 2 sizes smaller on the mainjet.

Johnny

Thanks for the feedback, guys.

Johnny, I agree with you about the base diameter. My measurements say that the JD red is about equal to a "K", so the "L" series needles (CEL/CCL/EEL) should be 1 click leaner on the base. A CEM might be interesting to try too! I may try that out after I run the other needles that I bought.

The reason that I was considering running a "D" series taper (DCL/DDL) is because that more closely matches the taper angle of the JD Red needle. I was hoping that because of that I would not need to change the main jet. I am trying to get rid of the low speed bludder and improve my throttle response in the woods.

I am also using the G2 400 throttle cam, I like it a lot in the tight stuff!

Tried my bike with the JD Red in the 1st clip today and I didn't like it. It cleared up the light throttle burble/bludder, but it felt flat/lean when I opened it up to 1/4 throttle up through 1/2 throttle. I was definitely not comfortable with the way the bike felt.

So now I am searching for a needle with a similar angle and length-to-taper as the JD Red, but with a larger straight diameter. Maybe a DCL (have one on order) or a DCM? JD said they might have something for me to try too...

Your just thinking about it too much,I know when lean is too lean. I does not run lean anywhere in the range with the CEL. I makes more smooth power right off the bottom and rips all the way to the top, I ring the piss out of mine and my plug readings are perfect. And I know lots of others who run the cel with same results. Try a 42p 170m CEL 3rd clip air screw 1 and3/4. you will be spot on and I guarantee you will love it. (that is if you like a strong motor compared to a flat doggy motor with the jd needles

The CEL is very good, but i will try the CEM too as it's quite warm here in Sweden now. I prefer to run my bike quite lean in the woods to get a smooth traNSITION WHEN I GO ON THROTTLE IN THE GNARLY SLIPPERY STUFF. cLEANER RUNNING, NO CLOGGED PLUG AND LESS WHEEL SPIN. Damn caps lock:=)! I have the CEM in my Honda CR 500 now, but i will take it out and try it in the Husky for sure. We have around 20 degrees C at sealevel here and i run the red JD in 1st clip, 40 pilot and 175 main now with a 7 slide. I will try the CEM in 2nd clip . I only us the EEL for iceracing to be safe on the looong straights:=). We go up to 90 mph there, and it's WOT for a long time.

I wonder if we should be looking at the D-taper needles instead of the C-tapers. The taper angle of the JD Red is ~1.9 degrees, the C is 1.5, and the D is 1.75. Seems like the D should be a safer bet, and probably still not too rich.

I have a DCL in the mail, hopefully will be here for some testing this weekend. The "D" should be a compromise taper between the JD Red and the CEL, the "C" means it's a few clips richer, and the "L" should help with the off-idle richness. I wish I had also ordered a DCM!

WHOOPS! I made a mistake in my earlier calculations, with regard to the "L1" dimension on the Keihin needles (the 2nd digit in the part number). Because of that, it looked they everything was leaner than it actually is. I didn't figure it out until I measured the Keihin needles that I ordered!

So, now I have the right measurements. The CEL and the JD Red both start tapering at the same place (thus should be relatively similar as far as clip position. However, the CEL is bigger base diameter, and is a less steep taper, so it will be leaner than the JD as the throttle opening gets larger.

A DEK or a DDK are probably the closest match to the JD Red.

I am going to try a CEL (sorry it took me so long to come around!) and I have a DCL that I think I will try. The D"C"L is probably a bit too rich as far as clip position, I suspect I will need to run it in the top clip, it's 2 clips richer than the CEL, basically. It does have the larger base diameter, though. I have a CCL, which is the same as a CEL but 2 clips richer, so I can try running that in the top clip, should be the same experience as a CEL in the middle.

I wonder if we could go even larger on the base diameter, say up to M...

I will try the CEM soon. I think the CEM in 2nd clip is a good choice to clean up the idle and 1/8 throttle, but also get the response when you give it a bit more throttle. I like the PWK in these bikes, it's only a jetting thing to get it perfect. I have ordered a Lectron 48mm, but not for this bike:=). There are no big PWK, s out there!

Ok, I used the JD jetting sheet to compare some of the different needles we've been talking about:

JD Red - Very similar to EDK
JD Blue - Very similar to DDH
CEL
DEL (similar to CEL but with more taper angle)

Both the JD red and blue can't be perfectly represented because they are triple taper, but these two needles mentioned above are actually a pretty good fit.

All of the needles are graphed in the 3rd clip, so adjust accordingly.



So, the JD blue is quite a bit richer than the red at low throttle opening, just like they say. It's actually a tad bit leaner up top because it is a little bit fatter (less angle than the red).

CEL is leaner than the red, especially around 1/4-3/8 throttle. A lot of guys run the red in the 2nd clip and the CEL in the third, and in that case the CEL is about the same as the red around quarter throttle, but leaner below (due to the larger diameter) and above (due to the shallower taper).

DEL is similar to the CEL but a bit richer up top because of the taper.

I also ran a CEM, it looks exactly the same as the CEL above about 1/4 throttle, but it is leaner around about 1/8 throttle because of the larger base diameter.

I am currently running the JD Red in clip 2 on my bike. I tried it in clip 1 but it was too lean. I am going to try a CEL and a DEL, I will probably try the DEL in clip 3 first.

I tried the DEL on my bike and it wasn't as exciting as I thought it might be. It felt a bit leaner at lower throttle, but overall the bike really didn't feel much different. I was expecting a significant change in engine feel and/or throttle response, but I didn't really get it.

In the end it felt a little bit leaner than I would like (although it was probably fine) so I went back to the JD red. Right now I am running the JD red on the 3rd clip because it is getting a little bit cooler out here; it's probably a bit on the rich side though.

I have a big ride coming this weekend (2 days) so I think I will try a few different needles at that. I am going to start out with a CEL in the middle clip (should I go one clip richer for colder weather?), and then the JD red in a few different positions.

I will be there too on Sunday, if your going to the Hammer Run that is, (do you ride with Racin Mason, Dan S and their group?? they are friends of mine but major speed difference) I run a PWK A/S on my '11 300 but have a YZ250 needle in it right now (think it is a N3EJ) It's pretty clean but I'm no jetting expert at all. So to say the least I'm very interested in your finding for sure!!!

Yup, Hammer. I do not ride with those guys. I will be with a big crew, we'll have my WR300, my TE610, a TE450 and a TXC250, and a bunch of orange bikes...

I have a pwk 36mm that runs real well with a R 1469 needle - not sure how it compares to yours but it works well for me. Think its an older suzuki RM250 or 125 needle.
I also tried the N7NW kx needle

Well, I finally got around to trying the CEL needle in my '12 WR300. My setup is a stock motor, FMF pipe, Maxima Super-M at 40:1, 172 main, 42 pilot, CEL 3rd clip. I ran this setup for an entire enduro (~80 miles) yesterday in about 40-50 degree temps, lots of 2nd and 3rd gear sandy trails.

I didn't really like the change. It was subtle, but the bike had less grunt right off idle. With the old setup (JD red), it had lots of instantaneous torque right off idle, which I use a lot because I tend to run the bike a gear high in the woods, and the snappy response is good for lofting the front wheel over stuff. It seemed to be a little bit less "snappy" right off idle with the CEL.

In addition, the motor was making some unhappy noises that I was not a fan of. I don't know if it was detonation or piston slap or what, but at low revs it would occasionally "clank" or "clunk" at low throttle transitions. Anyone have any ideas as to what this might have been? I'm sure it's not good.

I will be going back to the JD red needle for my next race.

Any idea where the DDJ needle falls into thats what mine has in it